Thank you Gunther. I'm sorry I have frustrated everyone. Really I
thought the pet store would know given the huge size of their fish
area and the fact that the staff seemed very interested and offered
what I thought were rational options. It seems to me if the 1 fish to
10 gall rule is critical that it would be more mentioned outside of
listservs.

I will say to the 6" growth I was told they won't grow unless you get
a bigger tank, so I felt safe. That being said, 10 gallon is not out
of the question. Perhaps I can move Goldie to that and get a Betta for
the smaller tank (which seems certainly large enough given the size of
those golf ball size tanks they are kept in at the store).

Goldie, btw, is covered in a lot of black spots but seems happy,
eating and swimming. I have not done daily water changes as the levels
seem fine and the water is clear. I will continue to monitor the
situation.

Thanks
Marie